In various manufacturing environments, workpieces big and small are secured in fixtures prior to being processed (e.g., machined, drilled, sanded, welded, painted, etc.). However, fixturing large workpieces has proven to be particularly difficult and, thus, expensive due to the need for multiple precisely positioned contact points between the fixture and the workpiece, while preserving the ability for equipment and personnel to access the workpiece.
For example, aircraft, such as large commercial jetliners, are typically assembled from multiple large, separately-manufactured components (e.g., wings, empennage and multiple fuselage sections). During the manufacturing process, aircraft components must be rigidly supported to facilitate the various processes that must be performed to yield the finished component.
Traditionally, so-called “bed of nails” fixtures were used to support large, non-planar workpieces, such as aircraft wing skins. A typical “bed of nails” fixture includes multiple support posts positioned at various locations below the workpiece, thereby elevating the workpiece over the underlying floor. The support posts may linearly extend and retract (vertical movement) such that each support post contacts the workpiece at a contact point and elevates that contact point to the desired height. However, traditional “bed of nails” fixtures offer little or no horizontal movement of the support posts. Therefore, traditional “bed of nails” fixtures are not readily and efficiently reconfigurable to accommodate various different workpieces. When “bed of nails” fixtures are made to be reconfigurable, they have many unused support points (pogos). Traditional “bed of nails” fixtures are also composed of many support posts that are not used in any given setup due to the fact that the support posts used in one configuration cannot be used in other configurations.
Furthermore, some “bed of nails” fixtures allow for a bank of support posts to move along a linear guide or to move the entire bank along another axis. However, the reconfigurability is limited and does allow for rotation.
Accordingly, those skilled in the art continue with research and development efforts in the field of workpiece fixturing.